Paint spraying machine



v June 17, 1941. w. G. MILLER PAINT SPRAYING MACHINE 6 Sheets-Sheet lFiled Jan. 10,' 1958 JEH.

June 17, 1941. w G. MILLER PAINT SPRAYING MACHINE 6 Sheets-Sheet 2 FiledJan. 10, 1938 Qleazx.

A TTORNEYS.

6 Sheets-Shea?l 3 w. G. MILLER Filed Jan'. 1o, 1958 PAINT SPRAYINGMACHINE June 17, 1941.v

June 17, 1941. w. G. MILLER PAINT SPRAYING MACHINE Filed Jan. 1o, 193e 6Sheets-Sheet 4 bNL (NNN June 17, 1941.' w GA, M|| ER 2,245,932

PAINT SPRAYING MACHINE 'Filed Jan. 10, 1938 6 Sheets-Sheet 5 a? 1NVENTOR BY f 6. fill/n A TTORNE yes.

June 17, 194.1. w, G, M|LLER 2,245,932

PAINT SPRAYING MGHINE Filed Jan. 10, 1938 6 ShveetsbSheet 6 PatentedJune 17, 1941 PAINT SPRA'YING MACHINE william G. Miller, neu-oit, Mich.,assignor to The R. C. Mahon Company, Detroit, Mich., a corporation ofMichigan Application January 10, 1938, Serial No. 184,148

11 Claims. (Cl. 91*45) I This invention relates to machines for autoamatically painting irregularly shaped articles and is particularlyadapted for painting automobile bodies.

The main objects of this invention are to provide an improved paintspray machine which has a wide range of operation; to provide a paintspray machine which will maintain the Spraying nozzle a predetermineddesired distance from the surface of the objectbeing painted; to providea paint spray machine which may be readily changed to paint diierentlyshaped objects having a wide range of contour particularly in the matterof vertical height; to provide a paint spray machine which will maintainthe spray nozzle substantially perpendicular to the surface beingpainted; to provide a paint spray machine which will apply a uniformcoat of paint free from objectionable overlaps which might cause thepaint to run; to provide an improved paint spray machine which willimmediately cease applying the paint should the object being paintedstop its movement through the machine; to provide an improved paintspray machine which may be readily synchronized with a conveyer line soas to maintain a continuous operation for maximum production; to providea paint spray machine of wide utility and of simple and sturdyconstruction, and to provide a paint spray machine which will requirerelatively little powerl to operate due to the counterbalancing of themain moving part.

An illustrative embodiment of this invention is shown in theaccompanying drawings, in which:

Fig. 1 is a view in side elevation of the improved machine in full linesand with a fragmentary portion thereof shown in dotted lines in aposition to paint the lower rear end of an automobile body.

Fig. 2 is a view in end elevation of the'same, taken from the positionof the line 2-2 of Fig. 1 and looking in the direction indicated by thearrows.

Fig. 3 is a top plan view of the same. Fig. 4 is 'an enlarged viewpartly in section an showing the carriage supporting and paint nozzlepositioning tracks in elevation, the section being taken along the line4 4 of Fig. 1.

view taken along the line 1-1 of Flg. 5, looking in the directionindicated by the arrows.

Fig. 8 is a sectional view taken along the line 8 8 of Fig. 7, lookingin the direction indicated by the arrows.

Fig.VV 9 is an enlarged fragmentary sectional view taken along the line9-9 of Fig. 3, looking in the direction indicated by the arrows.

l Fig, 10 is a view similar to'Fig. 7, but with the solenoids energizedto raise the trigger control track so that paint 'will be sprayed fromthe.

nozzle when the carriage is moved inwardly from the ends of itstrackway. Fig. 1l is a fragmentary sectional View, taken along the lineII-II of Fig. 1'0, looking in the direction indicated by the arrows.

linv the particular mechanism herein illustrated a supporting structurecomprising a pair of horizontally spaced vertically disposed fabricatedstructures, generally designated I5 and I6 in Fig. 2 of the drawings,are shown positioned in spaced relation at opposite sides of a conveyertrackway I'l. The track is adapted to have wheel cars or dollies I8 passtherealong, and it is customary to have the dollies moved by a linkchain I9 shown most clearly in Figs. 2 and 6v of the drawings.Automobile bodies 20 are shown carried by the dollies I8, but it will beunderstood that the mechanism and apparatus herein shown and describedis equally well adapted to the painting of a wide variety of articles orobjects Fig. 5 is a sectional view taken along the line and is in nowise hunted to the painting of automobile bodies.

The supporting structures I5 and IB are of substantially identicalconstruction and comprise a plurality' of vertically disposed posts 2|,which. in the embodiment shown, are heavy angles and which are arrangedin spaced relation one at each corner of a rectangular shaped structure.Horizontally disposed top and base members 22 and 23 respectively havevtheir respective ends secured to the upper and lower ends of thevertical posts 2| respectively by gusset plates 24. Suitable diagonalbraces 25,v also formed of angle iron, are riveted to the gusset platesso as to give longitudinal rigidityl to the structure in a plane normalto it, as viewed in Fig. 1 of the drawings.

Diagonally disposed braces 26 are riveted to the inwardly extendinganges of the corner posts 2|, as best illustrated in Fig. 2 of thedrawings. for imparting lateral rigidity to the fabricated structure.

It will be understood, of course, that these vertically disposed spacedsupports may be formed from any suitable material and by any desiredconstruction or may be part of the bullding structure in which the paintmachine is housed, as the sole purpose and function of these structuresare to support the operating movable mechanism hereinafter to bedescribed.

The space between the vertical supports I5 and I6 is spanned by a jackshaft 21, one end of which is journaled in axially spaced bearing boxes28 and 29 mounted on the top horizontally disposed members of thesupporting struc-ture I5, and the other end of which is journaled inaxially spaced bearing boxes 30 and 3| similarly mounted on the top ofthe supporting structure I6.

The jack shaft 21 supports and has pivotally mounted thereon asuperstructure generally design-ated 32 in Fig. l. The superstructure 32is substantially rectangularly shaped in plan view and is formed by apair of spaced parallel truss members generally designated 33 and 34 inFig. 3 of the drawings, and which are held in such position bytransverse members 35, 36, 31 and 38. which are rigidly secured to theside trusses by rivets and gusset plates in the usual manner offabricating structures of this character. Diagonals 39 and 40 are alsoprovided for imparting rigidity to the structure and a medial brace 4Iis also provided, one end of which is riveted to the gusset plate 42secured to the cross member 35, and the other end of which is riveted toa gusset plate 43 which is secured preferably by Welding to the crossmembers 36 and 31.

As shown most clearly in Fig. l of the drawings, each side trusscomprises a base member 44 of channel cross section, a pair of inclinedmembers 45 and 46, one end of each of which is secured to the respectiveopposite ends of the base member 44, and the other ends of each of whichis secured to the upper end of a vertical post 41, the lower end ofwhich is secured to the medial par-t of the base member 44 by rivetingtwo gusset plates 48 and 49 at the upper and lower ends respectively ofthe post 41.

The left end of the superstructure, as viewed in Fig. l of the drawings,is provided with a motor and reduction gear support fabricated from aplurality of plates and angles, and generally designated 50.

The superstructure is journaled on the jack shaft 21 by means of journalbearing boxes 5| and 52 which are bolted to the upper surfaces of thebase members 44 of the side trusses 3 3 and 34 respectively. Short anglebars 53 are welded to the inner sides of the base members 44 with oneflange thereof extending in alignment with and disposed oppositely tothe top ange of the base member so as to provide a good bearing seatupon which the bearings 5I and 52 are bolted.

The bearing boxes 5I and 52 are located adjacent to one end of thesuperstructure but are spaced inwardly from such adjacent end so thatthe motor and reduction gearing mechanism mounted on the support 50serve as a partial counterbalance for the superstructure.

At the apex of the side trusses, the cross members 36 and 31, oppositeends of which project beyond the sides of the superstructure, carrybearing journal boxes 54 and 5.5 bolted to end pla-tes 56 and 51respectively which are welded to the projecting ends of the crossmembers 36 and 31. A bea-ring journal box 58 is also bolted to the topsurface of the gusset plate 43 and the three bearings 54, 55 and 58 areln axial alignment and have journaled therein a cam follower shaft 59,the opposite ends of which project beyond their respective end bearingsand have rigidly keyed thereto double flanged roller Wheels 60 and 6I.

The rollers 60 and 6I ride upon and their flanges embrace opposite sidesof vertically disposed duplicate contour cams 62 and 63 respectivelywhich are journaled on horizontal transversely disposed countershafts 64and 65 respectively. The countershaft 64 is journaled in a pair ofaxially spaced bearing journal boxes 66 and 61 which are bolted to thetop of the supporting structure I5 in spaced parallel relation to thebearing boxes 28 and 29 in which jack shaft 21 is journaled. Likewisethe countershaft is journaled in a pair of axially spaced bearingjournal boxes 68 and 69 which are bolted to the top of the supportingstructure I6 in spaced parallel relation to the jack shaftbearing boxes30 and 3|.

1 Means are provided for rotating the contour cams 62 and 63 so as toswing the outer free en'l of the superstructure in a vertical plane andcomprise an electric motor |00 geared to an adjustable speed box I0|which in turn drives a worm gear reduction unit |02. Shaft |03 of theworin reduction gear has a chain sprocket |04 keyed thereto whichreceives a roller link chain |05 which passes around and drives thechain sprocket |06 keyed to the jack shaft 21. shaft 21 at pointsclosely adjacent to the outer bearing boxes 28 and 3| has keyed theretorelatively small sprockets |01 and |08 respectively which receive anddrive chains |09 and I I0 respectively. The chains |08 and IIO passaround and drive relatively large chain sprockets I I I and I I 2respectively which are keyed to shafts 64 and 65, thus transmitting arelatively slow drive to the contour cams 62 and 63 which are likewisekeyed to the shafts 64 and 65.

The end of the superstructure opposite to that which is pivotallymounted to the space supports has a cross head, generally designated 10in Fig. 3 of the drawings, plvotally mounted between the projecting ends1| and 12 of the side trusses 33 and 34. The cross head 10, as shownmost clearly in Fig. 8 of the drawings, comprises a horizontallydisposed upper channel member 13 and a horizontally disposed lowerchannel member 14, both having their flanges extending upwardly, whichare rigidly secured in spaced parallel relation by verticallydisposedend channels 15 and 16 and angle irons 11 riveted thereto, and thusorming a rectangular structure having top and bottom and ends but withthe sides open. The end channels have their anges disposed outwardlywith respect to the structure.

The upper member 13 has its opposite ends projecting beyond the verticalend channels 15 and 16 and have journal bearing boxes 18 and 19 boltedtheretoin which are journaled one end respectively,'of short stub shafts80 and 8|, the other respective ends of which are journaled in bearingboxes 82 and 83 respectively which are bolted to angle brackets 84 and85 respectively and which are welded to the projecting ends 1I and 12respectively of the side trusses.

Means are provided for rocking the cross head 10 on its pivotal supportand comprise a pair of stub shafts 86 and 81, one end of each of whichis journaled in bearing boxes 88 and 89 respectively which are bolted tothe lower cross head member 14. The other end of each of the shafts 86and 81 are journaled in bearing boxes 90 and 9|. The bearing journal box90 is rigidly bolted The jack to one end of a connecting rod 92,-and thejournal bearing box 9| is bolted to one end ofva channel shapedconnecting rod 93.' 'Ihe opposite end of the connecting rod 93 has ajournal bearing box 94 bolted to the underside thereof in which isjournaled one end of a stub shaft 95, the other end of which'is rigidlymounted in the end 86 of a bell crank lever 91 which oscillates on afixed pivot 98 by means of a rigidly mounted stub shaft 99 which isjournaled in a bearing box ||5 rigidly bolted to the motor andtransmission support 50. The other arm of the bell crank has va doubleflanged roller ||6 journaled betweenv the outer ends thereof which isarranged to embrace opposite sides of and ride upon the periphery of afocusing cam ||1.

The cam ||1, as shown most lclearly in Fig'. 9 of the drawings, ismounted on a hub ||8 which has a bushing I9 and which is journaledloosely on the jack shaft 21. The other end of the hub ||8 is shaped toprovide an integrally formed chain sprocket |20 which receives a drivechain |2|. The chain |2| also passes around and is driven by a chainsprocket |22 which is keyed to the shaft 64 on an end thereof whichprotrudes inwardly from its bearing box 61, the sprockets |22 and |20being of the same size so that the focusing cam H1 and the contour cam52 are driven in synchronism' and at a one to one ratio.

A helical tension spring |23 has one end thereof secured to theconnecting rod 93 and the other end thereof anchored to the base member44 of the side truss and is under tension at all times so as to swingthe connecting rod to the left, as viewed in Fig. 1 of the drawings, andthereby maintain contact of the roller ||6 with the periphery of thefocusing cam ||1.

Likewise the opposite end of the connecting rod 92 has a journal bearingbox |24 rigidly bolted thereto in .which is journaled one end of a stubshaft |25, the other end of which is rigidly mounted to'the end |26 ofone arm of abell crank lever |21.' 'Ihe bell crank |21 is journaled on axed pivot by a rigidly supported stub shaft |28 which is journaled inbearing box |29 bolted' to the side truss 34. The outer end of the otherarm of the bell crank |21 hasa dou-ble anged roller |30 journaledtherebetween which embraces opposite sides of and rides upon theperipheral edge of a focusing cam |3|.

tangular shape, a front plate |30 ofthe same shape held in spacedparallel relation to the back The focusing cam |3| is a duplicate of thecam |1 and is likewise mounted upon a hushed hub which carries anintegrally formed chain sprocket |32 which receives a drive chain |33.The chain |33 passes around and is driven by plate by short shaftsrigidly secured to the front and back plates near the four cornersthereof and lupon which are journaled four double hanged rollers|39,`|40, |4| and |42. The rollers |39 and |40 ride upon the top edge of'the track |36 with their flanges embracing the opposite side edgesthereof and the rollers |4| and |42 fit snugly against and bear upon thelower edge of the track |36 with their flanges embracing the oppositeside edges of the trackway, as shown most clearly in Figs. '1 and 8.

Means are provided for reciprocating the carriage from one end to theother of its supporting trackway and comprise an electric motor |43having a V belt pulley |44 on its armature shaft which drivesy a V belt|45. The belt |45 passes around and drives a V belt pulley |46 securedto one shaft of a speed reducer |41. The output shaft of the speedreducer |41 is provided with a double V belt pulley wheel which drivesbelts |48 which pass around and drive a similar pulley wheel secured toone end ofl a shaft |49 which is journaled in axially spaced bearings|50 and |5|. The bearings |50 and |5| are bolted to the top surface of apair of angles |52 and |53. Ihe angle |52 has its opposite ends rigidlysecured to the end channels 15 and 16, and the angle |53 is securedthereto so as to form a T section. with one endof the angle |53overlapping the side flange of the end channel 16 and secured thereto,and the other end thereof secured to the side ange of a verticallydisposed channel brace |54 which is rigidly secured to the side flangesof the upper and lower cross head channels 13 and 14 vsubstantiallymidway of their ends.

The opposite end of the shaft |49 has a double anged at belt pulleywheel |55 rigidly secured thereto which receives and drives a fiat belt|56. The belt |56 extends horizontally and passes around a double angedbelt idler pulley |51 which is rigidly mounted-on one end of a shaft|58.` The shaft |58 is journaled in axially spaced bearing boxes |59 and|60 which are bolted-to the top side of horizontally extending flangesof the angle |52 and an oppositely disposed angle |6| which is securedthereto to form a T section structure, one end of which overlaps and issecured to a side flangeof the end channel 15, and the other end ofwhich is rigidly secured to the side flange of the channel brace |54.

The belt |56 has a rectangularlyfshaped pin a chain sprocket |34 keyedto the inner protrading end of the shaft 65 so that the focusing cam |3|and contour cam 63 are driven in unison at the same speed.

A helical tension spring |35 is also provided for holding the roller |30in contact with the vfocusing cam |3|,. one end of the spring beingattached to the connecting rod 92 and the other respectivelyA and formsa carriage supporting' trackway.

A paint-spray nozzle supporting carriage isA reciprocably mounted on thetrackway |36 and comprises a -back plate |31 of substantially rec-Journaled therein, as shown most clearly in Fig. 1l. One end of the pin|63 is rigidly mounted in one end of a pitman arm |64, the other end ofthe pitman arm |64 has one end of a headed bearing Pin |65rigidlymounted thereon. The pin |65 extends through a hushed opening in arelatively thick center portion of the back plate |31 with the headVthereof on the inside of the back plate, as shown most clearly in Fig.8.

As shown most clearly in Fig, 11, the front face of the front plate |38is provided with a pair of vertically disposed slides or guideways |66and |61 mounted thereon in spaced parallel relation which embrace avertically movable slide plate |68, the marginal edges of which areembraced in opposed grooves |69 of the guides |66 and |61.

As lshown most clearly in Fig. 8, the lower end of 5 relationship to theplate |68.. The upper end of a roller |15 journaled on a headed pin |16which is rigidly mounted in a boss |11 formed on the face of the plate|68. The roller |15 rides on the top edge of a horizontally disposedcontour track |18 which is formed of a rectangularly shaped bar disposededgewlse and having its opposite ends bolted to the side anges of thecross head end channels 15 and 16 in spaced parallel relationshipthereto, filler blocks |19 and |80 being interposed. l

Means are provided for holding the slide plate roller |15 yieldingly incontact with the top edge of the contour track |18 at all times duringits reciprocation and comprise a helical tension spring |8|, one end ofwhich is anchored to a laterally extending ange |82 of an angle boltedto the top edge of the front carriage plate |38, and the other end ofwhich is secured to the top end of a vertically disposed brace member|83, the lower end of which is rigidly bolted to the top side of the webof channel |14, as shown most clearly in Fig. 8.

The inner opposed edges of the arms |12 and '|13 are vertically spacedparallel relation and serve as guides for a vertically movable triggerslide control which comprises a block |84, the opposite edges of whichare provided with outwardly presenting grooves which receive and embracethe opposed marginal edges of the arms |12 and |13. The rear side of theblock |84 is provided with a rigidly mounted headed pin |85 upon whichis journaled a roller |86, and the front :face of the block has avertically disposed arm |81 secured thereto by threaded studs |88 and|89.

The arm |81 extends downwardly from the slide block |84, and the lowerend thereof is provided with a transversely disposed nger or toe |90which is positioned to contact a roller |9| which is journaled on theouter end of a control trigger |92 of a paint spray nozzle |93.

The paint spray nozzle |93 is mounted on the front face of theupstanding part |1| of the vertically movable slide by hooking a bail|94 over a lug |95 which is mounted on the vertical slide |1| and heldin position thereon by the protruding end |96 of a vertically slidablepin |91 which is slidable in spaced bosses |98 and |99 formed on theupstanding member |1|. The handle 203 of the paint spray gun fits snuglybetween the boss |98 and a lug |98A, which embrace opposite sidesthereof.

That portion of the pin |91 which is between mounting bosses |98 and |99is surrounded by a helical compression spring 200, the lower end ofwhich abuts against and rests upon the boss |99, and the upper end ofwhich bears against an enlarged head 20| formed on the upper end of thepin so as to normally urge the pin upwardly to the position shown inFigs. '7 and 8. The pin extends below the lower boss |99 and is providedwith an enlarged head 202 which may be conveniently grasped by anoperator for pulling the pin downwardly against the action of the spring200 so as to release the handle portion 203 of the paint spray gun andpermit it to be unhooked from the lug |95.

Compressed air is supplied to the spray gun through a ilexible pipe 204and paint' is supplied through' a flexible pipe 205, the spray gun as awhole being of somewhat standard design and character with only slightmodifications to adapt it for use in this particular environment.

Means are provided for actuating the trigger |92 through the toe |90,arm |81, slide block |84L and roller |86, and comprises a trackway 206which is mounted in spaced parallel relationship to the contour track|18. The track 206 is contoured simllarly to the track |18 except thatat the opposite ends thereof the top edge upon which the roller |86rides is vertically spaced below the top edge of the contour track |18 agreater amount than that portion of the trackway which is inward fromthe ends. The track 206 is mounted on the outer face of a spacer bar 201which is secured to the outer face of the contour track |18 and isvertically slidable thereon by reason of vertically disposed mountingslots 208 which receive the headed end of threaded studs 209 which arescrewed through the spacer bar 201 and into the contour track |18.

Means are .provided for raising the trigger control track 206 andcomprise a pair of solenoids 2|0 and 2|| mounted at opposite ends on thefront side of the cross head and having vertically movable cores 2|2 and213 respectively, the lower ends of which are pivotally connected to theupper ends of links 2|4 and 2I5 respectively. The other end of link 2|4is connected to one end of a substantially horizontal lever |26,

.the other end of which is pivoted to the upper end of an upright link 21, the lower end of which is mounted on a xed pivot 218 of the crosshead. The medial part of the lever 2|6 has the upper end of an uprightlink 2|9 pivoted thereto, the lower end of which is pivotally connectedto one end of the trigger control track 20B.

'I'he lower end of the link 2|5 is connected to one end of asubstantially horizontal lever 220, the other end of which is pivoted tothe upper end of an upright link 22|, the lower end of which is mountedon a fixed pivot 222 on the cross head frame. The medial part of thelever 220 is pivotally connected to the upper end of an upright link223, the lower end of which is pivotally connected to the opposite endof the trigger control track 206.

Means are provided or moving the conveyer chain I9 and comprise anelectric motor 224, which, through 'the medium of a speed reducer 225,drives a shaft 226 journaled in bearings 221 and 228 and which carriesat its medial part a chain'sprocket 229 around which the conveyer chainI9 passes.

Current is supplied to the motor 224 through the conductors 230 andV23|, a switch 232 being provided in the conductor 23| for opening thecircuit and thereby stopping the conveyer line when desired. Theconductors 230 and 23| also carry current to conductors 233 and 234which supply current to the carriage operating motor |43.V A switch 235is provided in the conductor 23| so that the circuit from that point onmay be opened without stopping the conveyer mechanism.

The conductors 230 and 23| also have bridged thereto a pair ofconductors 238 and 231 which supply current tothe solenoids 2|0 and 2H,a switch 238 being provided for securing individual control of thiscircuit. The main circuit is also extended and supplies current to themotor |00 which drives the focusing cams and contour cams, and a switch239 is also provided for securing individual control of the motor |43.

In the operation of this machine the duplicate contour cams 62 and 13are laid out and made in [such shape as to hold the free swinging end ofthe superstructure and paint spray nozzle carried thereby apredetermined distance from the surface of the object to be painted,such as an automobile body, as such object is passed beneath thesuperstructure by the conveyer. In the particular example shown, therollers 60 and 6| which control vertical swinging movement of thesuperstructure rest on their respective contour cams at about the pointmarked by the arrow 238, as shown in Fig. l, when the cowl of theautomobile is in position to begin painting. 'I'he conveyer and paintmachine are operated at the same time and are so synchronized that asthe contour cams rotate, the object to be painted is passed along underthe cross head of the superstructure and the paint spray vnozzle ismaintained in predetermined distance from the object to be painted. Atthe same time the duplicate focusing cams ||1 and 83| are rotated in.

unison with the contour cams and through the medium of the bell cranksand the connecting rods 92 and 93, the cross head 10 is rocked on itspivotal supports so as to maintain the paint spray nozzle substantiallyperpendicular to the surface being painted in a vertical longitudinalplane.

When the superstructure has been moved to its initial starting positionby rotation of the contour cams 62 and. 19, the manually operable switch235 is opened, and the conveyer, by closure of the switch 232, continuesto operate to bring the "object to be painted into correct startingposition. At this time the switch 235 is closed as well as the switch238 which controls the circuit to the solenoids 2|0 and 2|| and theswitch 239 which controls the carriage operating mo-A tor |43, whereuponthe motor ,is started, the carriage operating motor |43 isstarted andthe solenoids 2|0 and 2|| are both energized.

Energizationv of the solenoids will raise their respective coresupwardly and through the system of linksand levers connected theretowill raise the vertically movable trigger operating track 206 from theposition shown in Fig. 7 of the drawings to the position shown in Fig.10. When the track 206 is raised to the position shown in Fig. 10,the`rol1er' |86 which rests thereon raises the slide |84, depending arm|81, and toe |90, which in turn lifts the trigger |92 upwardly but notsuiciently to turn on the supply of the object to be painted, but whenthe carriage approaches the end limits of, its track,`the relativevertical distance between the top edges of the tracks |18 and 208 issuch that the supply of paint and compressed air is cut off.

Should the conveyer line which is carrying the objects to be paintedthrough the paint machine, be stopped at any time by opening of theswitch 232, this will automatically stop the motors |00 and |43 andcie-energize the solenoids 2|0 and 2| and thereby immediately cut of!the supply of paint and compressed air to the nozzle so as to not buildup an objectionable thickness of paint at one spot on the objectbeingpainted while the conveyer line is at a standstill.

These machines are ordinarily adjusted so as to spray a very heavy butuniform coat ofV paint on j the objects being painted, and if the supplyof compressed air and paint to the spray nozzle when the carriage isadjacent the respective ends of its track. As will be seen most clearlyin Fig. 10, the. vertical distance between the top edge yof the track|16 and the top edge of the track 206 is materially greater at thehorizontal end portions than such distance is ata point inward from itsends and where the tracks begin to take the contour of the article orobject to be painted. This is also clearly illustrated in Fig. 4

paint 4was not discontinued upon stopping of the conveyer line, thepaint would quickly accumulate to the point where it would flow and thusspoil the job.

Closing of the circuit to the motor |00 causes it to drive the speedreducer unit |0|, which in 'the relative large sprocket wheels and ||2which are keyed to the shafts 64 and 65 respectively. Rotation of theshafts 64 and 65 rotate the contour cams 62 and 63 respectively and uponwhich rest the rollers 60 and 6| of the cam follower shaft 59. The shaft59 is journaled on and supports the superstructure which is pivotallysupported on the jack shaft 21 as va xed axis, and thereby rotation ofthe cams will swing the opposite end of the superstructure, i. e. theone which carries the cross head 10 in a vertical plane in accordancewith the shape ci' the contour cams.

Shafts 64 and 65 have keyed thereto sprockets |22 and |23 respectivelywhich drive chains |2| and |33 respectively. These chains pass aroundand drive sprockets |20 and |32, respectively. which are integrallyformed at one end oi' hubs at the opposite ends of which are carriedthe. A

painted when considered in a vertical longitudi nal plane.

Closing of the circuit to the carriage operating motor |43 will causeactuation of the speed. reducer |41 which, through the medium of the Vbelts |48 and shaft |49, will rotate the double ilanged belt pulley v|55and thus move the belt |56 which passes therearound and which passesaround the idler |51. Movement of the belt |56 will carry the pitman arm|64 with it and thus I cause reciprocationof the carriage, to which itis connected, upon the track |38 from one end thereof to the othercontinuously while the motor |43 is energized.

If the solenoids 2|0 and 2|| are not energized during the reciprocationof the carriage on its track, the paint will not be sprayed from thespray gun by reason of the fact that the trigger |92 is not raisedsuillciently relative to its point of mounting, but if the solenoids areenergized and the trigger control track 206 thereby raised, then thetrigger will be moved sufficiently by its connecting mechanism throughthe medium of the roller |86 riding on the top edge of the track 206, tocause paint to be sprayed from the nozzle except at those portions ofthe tracks adjacent the ends thereof. Cutting off of the supply of paintat the ends of the track will result in an even and uniform coat ofpaint being applied to all parts oi theobject being carried by theconveyer as well as save much paint which would otherwise be wasted.

In the event it is desired to spray a diierent color of paint on thenext succeeding object carried by the conveyer line, then the paintspray nozzle may be quickly removed by grasping the head 20| and pullingdown on the pin |91 against the action of the spring 200, then swingingout the handle portion 203 and unhooking the bail |94 from the lug |95.Asimilar spray gun having the desired color of paint therein may then bequickly hookedover the lug |95 and swung into place and there retainedby the upstanding end |86 of the pin, the handle portion 203 beingsnugly embraced between the boss |98 and thelug |98A which engages theupper side of the handle.

By adjusting the variable speed reducer IUI, the operating speed of thecontour and focusing cams and thereby vertical swinging movement of.

and paint machine may be so synchronid as4 to produce a continuousoperation of painting upon articles of similar contour when placed uponthe conveyer line in predetermined 'spaced relationship.

The circuit to the solenoids 2|0 and 2|| may be controlled also by `anelectric eye or some similar means whereby the spraying of the paintwill not be started until the object being painted is in correctposition with respect to the paint machine and will be immediatelydiscontinued when the object has passed therethrough and been completelypainted.

Although but one specific embodiment of this invention has been hereinshown and described, it will be understood that numerous details of theconstruction shown may be altered or omitted Without departing from thespirit of this invention, as dened by the following claims.

What is claimed is:

1. A paint spray machine comprising a supporting framework, asuperstructure mounted on horizontal pivots on' said s'pportingstructure and having a free end swingable in a vertical plane, a paintspray nozzle mounted on the free swinging end of said superstructure andmeans for swinging said superstructureV on its pivotal mounting formaintaining said spray nozzle a predetermined distance from an object tobe painted.

2. A paint spray machinel comprising a supporting framework, asuperstructure mounted on horizontal pivots on said supporting structureand having a free end swingable in a vertical plane. a paint spraynozzle pivoted on the free swinging end of said superstructure, acontour cam supporting the free swinging end of said superstructure, andmeans for rotating said cam for maintaining said spray nozzle apredetermined distance from an object to be painted.

3. A paint spray machine comprising a supporting structure, asuperstructure. pivotally mounted on said supporting structure andhaving a free swinging end, said structures being arranged so thatobjects to be painted may be moved along under said superstructure, apaint spray nozzle mounted on the free swinging end of saidsuperstructure for movement in a path transversely to the path of travelof the objects to be painted, means for moving said nozzle in its pathof travel,l a contour cam supporting the free swinging end of saidsuperstructure, means for rotating said cam for maintaining said spraynozzle a predetermined distance from the object to be painted and meansfor oscillating said nozzle relative to said superstructure on an axissubstantially parallel to the axis of movement of said superstructure.

4. A paint spray machine comprising spaced supports adapted to have aconveyer pass therebetween, a superstructure pivotally mounted on andbridging the space between said supports. contour cams ,iournaled onsaid supports and engaging said superstructure for controlling movementthereof on its pivotal support, a paint spray nozzle carried on one endof said superstructure and movable thereon in a path transverse to thepath of movement of the conveyer, and a focusing cam journaled on one ofsaid structures and driven in synchronism with said contour cam formoving said spray nozzle in a plane parallel to the direction ofmovement of the conveyor.

5. A paint spray machine comprising spaced supports adapted to have a,conveyer line pass therebetween, a superstructure pivotally mounted onand bridging the space between said supports. a trackway pivotallycarried on one end of said superstructure in spaced relation to saidpivotal support. a carriage reciprocable on said trackway, a paint spraynozzle on said carriage, means for moving said superstructure tomaintain said spray nozzle a predetermined distance from articles to bepainted thereby, and means for rocking said trackway to secure apredetermined angularity of said nozzle with respect to the surface ofthe article being painted thereby.

6. A paint spray machine comprising spaced supports adapted to have aconveyer line pass therebetween, a jack shaft journalled on and bridgingthe space between said supports, a superstructure pivotally supportedadjacent one end thereof on said jack shaft. a paint spray nozzlecarried by the other end of said superstructure, contour cams journalledon said supports and driven by said jack shaft for moving saidsuperstructure on its pivotal supports so las to maintain said nozzle apredetermined disstructure, a paint spray nozzle reciprocalble on saidtrackway in a path transverse to the path of travel of the conveyer,contour cams journalled on said supports and driven -by said jack shaftfor moving said superstructure on its pivotal supports so as to maintain,said nozzle a predetermined distance from the surface of objects to bepainted, a focusing cam journalled on said jack shaft and driven inunison with said contour cams, connections between said focusing cam andsaid trackway for rocking said trackway and nozzle independently of saidsuperstructure movement and means for driving said Jack shaft.

8. A paint spray machine comprising horizontally spaced supports, aconveyor line passing between said supports, a Jack shaft journalled onand bridging the space between said supports, a superstructure pivotedadjacent one end thereof on said jack shaft, contour cams journalled onsaid supports for supporting and moving the other end of saidsuperstructure in a vertical plane, a paint spraynozzle movably' mountedon said superstructure adjacent its vertically movable end, a focusingcam and connections for oscillating said spray nozzle on a horizontaltransverse axis and means for driving said contour and focusing cams insynchronism.

9. A paint spray machine comprising horizontally spaced supports, meansfor moving objects to be painted between said supports, a verticallyswingable superstructure pivoted on said supports ona horizontal axistransverse to the direction of movement of the objects to be painted, ahorizontally disposed trackway pivotally mounted on the verticallyswingable end of said superstructure on a horizontal axis substantiallyparallel to the axis of said superstructures pivotal mounting, acarriage reciprocable on said trackway. a paint spray nozzle carried bysaid carriage and means for vertically swinging said superstructure androcking said trackways in synchronism on their respective pivotalmountings whereby said nozzle will be maintained a predeterminedydistance from and at a predetermined angle with respect to the surfaceof ,irregularly shaped articles to be painted.

10. In a paint spray machine, a relatively straight horizontallydisposed track, a carriage reciprocable on said track, a spray nozzleholder vertically slidable on said carriage, a paint spray nozzle onsaid holder, a contoured track adjacent said straight track foractuating and positioning said nozzle holder, a trigger on said nozzlefor controlling the flow of paint through said nozzle, a third tracksimilarly contoured and adjacent to said second mentioned track foractuating said trigger, and means for shifting one of said contouredtracks relative to the other for actuating said trigger.

11. A paint spray machine comprising a supporting framework, asuperstructure swingably mounted on said supporting framework and havinga free swinging end, a paint spray nozzle pivoted on the free swingingend of said superstructure and bodily movable therewith, means formoving said superstructure on its mounting for maintaining said spraynozzle a predeter- ,mined distancefrom an object to be painted,

and independent means for moving said spray nozzle on its pivotalmounting to maintain said spray nozzle normal to the surface 0i' theobject to be painted.

WILLIAM G. MILLER.

